I bought a Kassai Magyar Sport bow at a pawn shop for $45 years back. It had water stains on the red leather and a few scratches. I told the guy that the water damage made the bow unshootable (I was dumb enough to think it might actually be horn and sinew, not effing-glass) so I got it for a song.
Unless you are trying to historically re-create a period in time and/or a historical character, your choice in finishing out the bow is purely up to your imagination! I think a set of snakewrappers would look incredible on the bow. But then, so would sturgeon skin, turtle skin, carp skin, or even a bunch of bullfrog hides if you got the patience to blend them together.
As for the yarn siyahs and the wrap....are you going to be wrapping the transitions from limb to siyah? Is the wrap for aesthetics or is it functionally there to add strength? If it is just for looks, I would strongly advise you wrap with the lightest material and use only enough glue to get the tag ends to stay put. ANY nonfunctional weight added to a bow limb takes away from the performance and adds to hand shock on release.
Since I don't know what the limbs are composed of, or what the final choice of limb covering might be, I really can't say what glue to use.